xref: /qemu/bsd-user/qemu.h (revision 370ed600)
1 /*
2  *  qemu bsd user mode definition
3  *
4  *  This program is free software; you can redistribute it and/or modify
5  *  it under the terms of the GNU General Public License as published by
6  *  the Free Software Foundation; either version 2 of the License, or
7  *  (at your option) any later version.
8  *
9  *  This program is distributed in the hope that it will be useful,
10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  *  GNU General Public License for more details.
13  *
14  *  You should have received a copy of the GNU General Public License
15  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
16  */
17 #ifndef QEMU_H
18 #define QEMU_H
19 
20 #include "cpu.h"
21 #include "qemu/units.h"
22 #include "exec/cpu_ldst.h"
23 #include "exec/exec-all.h"
24 
25 #undef DEBUG_REMAP
26 
27 #include "exec/user/abitypes.h"
28 
29 extern char **environ;
30 
31 #include "exec/user/thunk.h"
32 #include "target_arch.h"
33 #include "syscall_defs.h"
34 #include "target_syscall.h"
35 #include "target_os_vmparam.h"
36 #include "target_os_signal.h"
37 #include "target.h"
38 #include "exec/gdbstub.h"
39 #include "qemu/clang-tsa.h"
40 
41 /*
42  * This struct is used to hold certain information about the image.  Basically,
43  * it replicates in user space what would be certain task_struct fields in the
44  * kernel
45  */
46 struct image_info {
47     abi_ulong load_bias;
48     abi_ulong load_addr;
49     abi_ulong start_code;
50     abi_ulong end_code;
51     abi_ulong start_data;
52     abi_ulong end_data;
53     abi_ulong start_brk;
54     abi_ulong brk;
55     abi_ulong start_mmap;
56     abi_ulong mmap;
57     abi_ulong rss;
58     abi_ulong start_stack;
59     abi_ulong entry;
60     abi_ulong code_offset;
61     abi_ulong data_offset;
62     abi_ulong arg_start;
63     abi_ulong arg_end;
64     uint32_t  elf_flags;
65 };
66 
67 struct emulated_sigtable {
68     int pending; /* true if signal is pending */
69     target_siginfo_t info;
70 };
71 
72 /*
73  * NOTE: we force a big alignment so that the stack stored after is aligned too
74  */
75 typedef struct TaskState {
76     pid_t ts_tid;     /* tid (or pid) of this task */
77 
78     struct TaskState *next;
79     struct bsd_binprm *bprm;
80     struct image_info *info;
81 
82     struct emulated_sigtable sync_signal;
83     /*
84      * TODO: Since we block all signals while returning to the main CPU
85      * loop, this needn't be an array
86      */
87     struct emulated_sigtable sigtab[TARGET_NSIG];
88     /*
89      * Nonzero if process_pending_signals() needs to do something (either
90      * handle a pending signal or unblock signals).
91      * This flag is written from a signal handler so should be accessed via
92      * the qatomic_read() and qatomic_set() functions. (It is not accessed
93      * from multiple threads.)
94      */
95     int signal_pending;
96     /* True if we're leaving a sigsuspend and sigsuspend_mask is valid. */
97     bool in_sigsuspend;
98     /*
99      * This thread's signal mask, as requested by the guest program.
100      * The actual signal mask of this thread may differ:
101      *  + we don't let SIGSEGV and SIGBUS be blocked while running guest code
102      *  + sometimes we block all signals to avoid races
103      */
104     sigset_t signal_mask;
105     /*
106      * The signal mask imposed by a guest sigsuspend syscall, if we are
107      * currently in the middle of such a syscall
108      */
109     sigset_t sigsuspend_mask;
110 
111     /* This thread's sigaltstack, if it has one */
112     struct target_sigaltstack sigaltstack_used;
113 } __attribute__((aligned(16))) TaskState;
114 
115 void stop_all_tasks(void);
116 extern const char *qemu_uname_release;
117 
118 /*
119  * TARGET_ARG_MAX defines the number of bytes allocated for arguments
120  * and envelope for the new program. 256k should suffice for a reasonable
121  * maxiumum env+arg in 32-bit environments, bump it up to 512k for !ILP32
122  * platforms.
123  */
124 #if TARGET_ABI_BITS > 32
125 #define TARGET_ARG_MAX (512 * KiB)
126 #else
127 #define TARGET_ARG_MAX (256 * KiB)
128 #endif
129 #define MAX_ARG_PAGES (TARGET_ARG_MAX / TARGET_PAGE_SIZE)
130 
131 /*
132  * This structure is used to hold the arguments that are
133  * used when loading binaries.
134  */
135 struct bsd_binprm {
136         char buf[128];
137         void *page[MAX_ARG_PAGES];
138         abi_ulong p;
139         abi_ulong stringp;
140         int fd;
141         int e_uid, e_gid;
142         int argc, envc;
143         char **argv;
144         char **envp;
145         char *filename;         /* (Given) Name of binary */
146         char *fullpath;         /* Full path of binary */
147         int (*core_dump)(int, CPUArchState *);
148 };
149 
150 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
151 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
152                               abi_ulong stringp);
153 int loader_exec(const char *filename, char **argv, char **envp,
154                 struct target_pt_regs *regs, struct image_info *infop,
155                 struct bsd_binprm *bprm);
156 
157 int load_elf_binary(struct bsd_binprm *bprm, struct target_pt_regs *regs,
158                     struct image_info *info);
159 int load_flt_binary(struct bsd_binprm *bprm, struct target_pt_regs *regs,
160                     struct image_info *info);
161 int is_target_elf_binary(int fd);
162 
163 abi_long memcpy_to_target(abi_ulong dest, const void *src,
164                           unsigned long len);
165 void target_set_brk(abi_ulong new_brk);
166 abi_long do_brk(abi_ulong new_brk);
167 void syscall_init(void);
168 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
169                             abi_long arg2, abi_long arg3, abi_long arg4,
170                             abi_long arg5, abi_long arg6, abi_long arg7,
171                             abi_long arg8);
172 abi_long do_netbsd_syscall(void *cpu_env, int num, abi_long arg1,
173                            abi_long arg2, abi_long arg3, abi_long arg4,
174                            abi_long arg5, abi_long arg6);
175 abi_long do_openbsd_syscall(void *cpu_env, int num, abi_long arg1,
176                             abi_long arg2, abi_long arg3, abi_long arg4,
177                             abi_long arg5, abi_long arg6);
178 void gemu_log(const char *fmt, ...) G_GNUC_PRINTF(1, 2);
179 extern __thread CPUState *thread_cpu;
180 void cpu_loop(CPUArchState *env);
181 char *target_strerror(int err);
182 int get_osversion(void);
183 void fork_start(void);
184 void fork_end(int child);
185 
186 #include "qemu/log.h"
187 
188 /* strace.c */
189 struct syscallname {
190     int nr;
191     const char *name;
192     const char *format;
193     void (*call)(const struct syscallname *,
194                  abi_long, abi_long, abi_long,
195                  abi_long, abi_long, abi_long);
196     void (*result)(const struct syscallname *, abi_long);
197 };
198 
199 void
200 print_freebsd_syscall(int num,
201                       abi_long arg1, abi_long arg2, abi_long arg3,
202                       abi_long arg4, abi_long arg5, abi_long arg6);
203 void print_freebsd_syscall_ret(int num, abi_long ret);
204 void
205 print_netbsd_syscall(int num,
206                      abi_long arg1, abi_long arg2, abi_long arg3,
207                      abi_long arg4, abi_long arg5, abi_long arg6);
208 void print_netbsd_syscall_ret(int num, abi_long ret);
209 void
210 print_openbsd_syscall(int num,
211                       abi_long arg1, abi_long arg2, abi_long arg3,
212                       abi_long arg4, abi_long arg5, abi_long arg6);
213 void print_openbsd_syscall_ret(int num, abi_long ret);
214 /**
215  * print_taken_signal:
216  * @target_signum: target signal being taken
217  * @tinfo: target_siginfo_t which will be passed to the guest for the signal
218  *
219  * Print strace output indicating that this signal is being taken by the guest,
220  * in a format similar to:
221  * --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
222  */
223 void print_taken_signal(int target_signum, const target_siginfo_t *tinfo);
224 extern int do_strace;
225 
226 /* mmap.c */
227 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
228 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
229                      int flags, int fd, off_t offset);
230 int target_munmap(abi_ulong start, abi_ulong len);
231 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
232                        abi_ulong new_size, unsigned long flags,
233                        abi_ulong new_addr);
234 int target_msync(abi_ulong start, abi_ulong len, int flags);
235 extern unsigned long last_brk;
236 extern abi_ulong mmap_next_start;
237 abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size);
238 void TSA_NO_TSA mmap_fork_start(void);
239 void TSA_NO_TSA mmap_fork_end(int child);
240 
241 /* main.c */
242 extern char qemu_proc_pathname[];
243 extern unsigned long target_maxtsiz;
244 extern unsigned long target_dfldsiz;
245 extern unsigned long target_maxdsiz;
246 extern unsigned long target_dflssiz;
247 extern unsigned long target_maxssiz;
248 extern unsigned long target_sgrowsiz;
249 
250 /* os-syscall.c */
251 abi_long get_errno(abi_long ret);
252 bool is_error(abi_long ret);
253 int host_to_target_errno(int err);
254 
255 /* os-sys.c */
256 abi_long do_freebsd_sysctl(CPUArchState *env, abi_ulong namep, int32_t namelen,
257         abi_ulong oldp, abi_ulong oldlenp, abi_ulong newp, abi_ulong newlen);
258 abi_long do_freebsd_sysctlbyname(CPUArchState *env, abi_ulong namep,
259         int32_t namelen, abi_ulong oldp, abi_ulong oldlenp, abi_ulong newp,
260         abi_ulong newlen);
261 abi_long do_freebsd_sysarch(void *cpu_env, abi_long arg1, abi_long arg2);
262 
263 /* user access */
264 
265 #define VERIFY_READ  PAGE_READ
266 #define VERIFY_WRITE (PAGE_READ | PAGE_WRITE)
267 
268 static inline bool access_ok(int type, abi_ulong addr, abi_ulong size)
269 {
270     return page_check_range((target_ulong)addr, size, type) == 0;
271 }
272 
273 /*
274  * NOTE __get_user and __put_user use host pointers and don't check access.
275  *
276  * These are usually used to access struct data members once the struct has been
277  * locked - usually with lock_user_struct().
278  */
279 #define __put_user(x, hptr)\
280 ({\
281     int size = sizeof(*hptr);\
282     switch (size) {\
283     case 1:\
284         *(uint8_t *)(hptr) = (uint8_t)(typeof(*hptr))(x);\
285         break;\
286     case 2:\
287         *(uint16_t *)(hptr) = tswap16((typeof(*hptr))(x));\
288         break;\
289     case 4:\
290         *(uint32_t *)(hptr) = tswap32((typeof(*hptr))(x));\
291         break;\
292     case 8:\
293         *(uint64_t *)(hptr) = tswap64((typeof(*hptr))(x));\
294         break;\
295     default:\
296         abort();\
297     } \
298     0;\
299 })
300 
301 #define __get_user(x, hptr) \
302 ({\
303     int size = sizeof(*hptr);\
304     switch (size) {\
305     case 1:\
306         x = (typeof(*hptr))*(uint8_t *)(hptr);\
307         break;\
308     case 2:\
309         x = (typeof(*hptr))tswap16(*(uint16_t *)(hptr));\
310         break;\
311     case 4:\
312         x = (typeof(*hptr))tswap32(*(uint32_t *)(hptr));\
313         break;\
314     case 8:\
315         x = (typeof(*hptr))tswap64(*(uint64_t *)(hptr));\
316         break;\
317     default:\
318         x = 0;\
319         abort();\
320     } \
321     0;\
322 })
323 
324 /*
325  * put_user()/get_user() take a guest address and check access
326  *
327  * These are usually used to access an atomic data type, such as an int, that
328  * has been passed by address.  These internally perform locking and unlocking
329  * on the data type.
330  */
331 #define put_user(x, gaddr, target_type)                                 \
332 ({                                                                      \
333     abi_ulong __gaddr = (gaddr);                                        \
334     target_type *__hptr;                                                \
335     abi_long __ret;                                                     \
336     __hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0);  \
337     if (__hptr) {                                                       \
338         __ret = __put_user((x), __hptr);                                \
339         unlock_user(__hptr, __gaddr, sizeof(target_type));              \
340     } else                                                              \
341         __ret = -TARGET_EFAULT;                                         \
342     __ret;                                                              \
343 })
344 
345 #define get_user(x, gaddr, target_type)                                 \
346 ({                                                                      \
347     abi_ulong __gaddr = (gaddr);                                        \
348     target_type *__hptr;                                                \
349     abi_long __ret;                                                     \
350     __hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1);   \
351     if (__hptr) {                                                       \
352         __ret = __get_user((x), __hptr);                                \
353         unlock_user(__hptr, __gaddr, 0);                                \
354     } else {                                                            \
355         (x) = 0;                                                        \
356         __ret = -TARGET_EFAULT;                                         \
357     }                                                                   \
358     __ret;                                                              \
359 })
360 
361 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
362 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
363 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
364 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
365 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
366 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
367 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
368 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
369 #define put_user_u8(x, gaddr)  put_user((x), (gaddr), uint8_t)
370 #define put_user_s8(x, gaddr)  put_user((x), (gaddr), int8_t)
371 
372 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
373 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
374 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
375 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
376 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
377 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
378 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
379 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
380 #define get_user_u8(x, gaddr)  get_user((x), (gaddr), uint8_t)
381 #define get_user_s8(x, gaddr)  get_user((x), (gaddr), int8_t)
382 
383 /*
384  * copy_from_user() and copy_to_user() are usually used to copy data
385  * buffers between the target and host.  These internally perform
386  * locking/unlocking of the memory.
387  */
388 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
389 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
390 
391 /*
392  * Functions for accessing guest memory.  The tget and tput functions
393  * read/write single values, byteswapping as necessary.  The lock_user function
394  * gets a pointer to a contiguous area of guest memory, but does not perform
395  * any byteswapping.  lock_user may return either a pointer to the guest
396  * memory, or a temporary buffer.
397  */
398 
399 /*
400  * Lock an area of guest memory into the host.  If copy is true then the
401  * host area will have the same contents as the guest.
402  */
403 static inline void *lock_user(int type, abi_ulong guest_addr, long len,
404                               int copy)
405 {
406     if (!access_ok(type, guest_addr, len)) {
407         return NULL;
408     }
409 #ifdef DEBUG_REMAP
410     {
411         void *addr;
412         addr = g_malloc(len);
413         if (copy) {
414             memcpy(addr, g2h_untagged(guest_addr), len);
415         } else {
416             memset(addr, 0, len);
417         }
418         return addr;
419     }
420 #else
421     return g2h_untagged(guest_addr);
422 #endif
423 }
424 
425 /*
426  * Unlock an area of guest memory.  The first LEN bytes must be flushed back to
427  * guest memory. host_ptr = NULL is explicitly allowed and does nothing.
428  */
429 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
430                                long len)
431 {
432 
433 #ifdef DEBUG_REMAP
434     if (!host_ptr) {
435         return;
436     }
437     if (host_ptr == g2h_untagged(guest_addr)) {
438         return;
439     }
440     if (len > 0) {
441         memcpy(g2h_untagged(guest_addr), host_ptr, len);
442     }
443     g_free(host_ptr);
444 #endif
445 }
446 
447 /*
448  * Return the length of a string in target memory or -TARGET_EFAULT if access
449  * error.
450  */
451 abi_long target_strlen(abi_ulong gaddr);
452 
453 /* Like lock_user but for null terminated strings.  */
454 static inline void *lock_user_string(abi_ulong guest_addr)
455 {
456     abi_long len;
457     len = target_strlen(guest_addr);
458     if (len < 0) {
459         return NULL;
460     }
461     return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
462 }
463 
464 /* Helper macros for locking/unlocking a target struct.  */
465 #define lock_user_struct(type, host_ptr, guest_addr, copy)      \
466     (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
467 #define unlock_user_struct(host_ptr, guest_addr, copy)          \
468     unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
469 
470 static inline uint64_t target_arg64(uint32_t word0, uint32_t word1)
471 {
472 #if TARGET_ABI_BITS == 32
473 #if TARGET_BIG_ENDIAN
474     return ((uint64_t)word0 << 32) | word1;
475 #else
476     return ((uint64_t)word1 << 32) | word0;
477 #endif
478 #else /* TARGET_ABI_BITS != 32 */
479     return word0;
480 #endif /* TARGET_ABI_BITS != 32 */
481 }
482 
483 #include <pthread.h>
484 
485 #include "user/safe-syscall.h"
486 
487 #endif /* QEMU_H */
488